I Would say it's from pychodus anonymus. Quite a strange tooth. I like fossil hunting on the Yorkshire Coast but the thing is you can only really find ammonites, bellemites, brachiopods, the odd fish fossils, and the occasional coral, and if you are extremely lucky, you can find ichthyosaur fossils and shark fossils. I'm going to redcarr in the spring: do I stand a good chance of finding an ichthyosaur fossil because the fossils there are 200 million years old which is the perfect age for an ichthyosaur fossil?

Thank's Dan and Quagga for your answers, although i have found sponges, echinoids, crinoides and ammonites from the cretaceous chalk as erratics on the Holderness this is the first shark/ray crushing plate I have witnessed.

I should have taked an image of the reverse because it is covered in bone.

You could be right on the cartilage, as for what I understand the only remains you usually find from a shark is the fin spine and the teeth but as it is something very rare from the Holderness I am open to any information at all.

I don't think it is the root. If you go on www.fossiliferous.co.uk and then go on sharks UK mozeoic, you will see fossil carterlage from the jaw which lookes simular. Also, the bone looks too small to be the root to me. I'm not sure on the species, but I thinkit looks different to the species quagga suggested.

When you say it had to be set in something do you mean it had to have been in a rock. Maybe it didn't actually come from chalk but shale. Usually the fossils from chalk are more white and fossils from shale can be a number of different colours.

That is a great specimen! The "bone" is without doubt the root of the shark tooth, I have collected a number of these from the chalk and all look similar to that. I agree with the ID of Ptychodus latissimus.

Thats's brilliant, thank you for the extra images. I have not heard of a Ptychodus tooth found as an arratic before. They are scarce enough in the chalk and to have one survive like this is just incredible.

It is quite a large shark tooth so would have been near the centre of the tooth palate. For obvious reasons it is fairly worn but this has brought out the beautiful internal structure of the tooth.

Thanks again for the pictures. I will be more than happy to help with your sponges.